Offnet to Offnet consult transfer doesn't work CCM 4.2(3)

Customer calls 1800 number. DNIS hits CTI routepoint and agent A picks up the call. Agent A presses the transfer key and dials PSTN number to transfer to third party. (Agent does a consult transfer here). Agent goes back to the customer and then hits the transfer key. But it doesnt work. when he presses the transfer key it triggers a third call.